Vintage Dirt Bike Q & A

I had the 78 cr250 stem pressed into my 83 triple clamps and then installed the new dust seal and lower bearing. I then knocked out the old races and drove in the new ones until they hit the stops.

When I went to trial fit the triple clamps it seems that I have a slight amount of play at the lower bearing. These are my questions:

1. Was I right to drive the lower race up to the point of stopping?

2. Or should I have left a small amount of space between the dust seal and lower bearing? They are right up against eachother now (No play).

Thanks for any help!

J

_________________
#829 The "Factory Novice"

1988 Honda CR250RJ
1983 Honda CR480
1981 Can-Am 250 MX6-B
1979 Honda CR250RZ
1979 Kawasaki KX250 A5
1978 Husky 250CR
1978 Honda CR250R
1977 Yamaha YZ400D
1977 Suzuki RM125B

Hey, J!!!

For what it's worth, I have a set of '84 forks, supposedly off a 480 (got off ebay), for my '79 Elsie. I went out to the barn and gave a quick look at each set of forks. Side question: How can you tell what model year of forks you have when get a used set like this? Aren't there some sorta differences in the damping adjustment(s)?

Anyway, to my eyes, they both appear to have the lower tapered bearing setting right down on black seal below the bearing. No hint of any sort of gap at all.....

Have you got that spanner nut tight enough that preloads the bearings???

How hard was it to press out the stem from your '78, and get it stuffed into your bigger forks? Is this pretty much a job for a hydraulic press?
Any tricks to getting it aligned straight?

_________________
Jimmie Newton
'79 XR500 (My project)
'99 XR100 Honda (Wife's bike)
'80 TT250 Yamaha (Son's Thumper)
Honda ATC 70 (Daughter's 3-wheeler)

Jimmie,

As far as I know the 43mm Showas were only made one year without front disc brake mounts (1983 CR250/480). The 1982 43mm Honda forks were Kayabas. They did have different adjusters.

I just used the force of my hand against the bottom of the triple clamps. Maybe the spanner nut would pull it in, but it seemed to be flush against the neck. ??

Yes the stem had to be pressed out of the old clamps and then pressed into the 83 clamps. The lower bearing also needed to be pressed on.

J

_________________
#829 The "Factory Novice"

1988 Honda CR250RJ
1983 Honda CR480
1981 Can-Am 250 MX6-B
1979 Honda CR250RZ
1979 Kawasaki KX250 A5
1978 Husky 250CR
1978 Honda CR250R
1977 Yamaha YZ400D
1977 Suzuki RM125B

The lower bearing and dust seal should be flush with the lower triple clamp. The lower race and upper race (and dust seal) seat against ridges in the frame so press or tap them in until the stop. Once the headset is tightened you should not have any play. Is the 1979 steerer secure in the 1983 lower triple clamp? I thought they used different mounting methods...

_________________
Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

With the forks and front wheel in place tighten the headset nut (under the triple clamps) until there is no play. Make sure the front-end still flops easily from lock to lock. When the headset is tight, tap the top triple clamp down to take up the slack and then tighten it and the top nut.

_________________
Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

Well this is becoming quite an experience. I mounted things up and I still have a small amount of play. The stem isn't perfectly straight, because I have some binding before it hits the stop.

The lower bearing and dust seal are flush against the bottom clamp. It's as if the bottom race is in too far (it came up against the stop) or should be deeper. Are the top and bottom bearings different? I hope it's that simple or I'm that stupid. LOL

So now I have two problems. This will have to wait until after the Thanksgiving trip. Anyone know a good Vintage/Evo mechanic in Bakersfield?

J

_________________
#829 The "Factory Novice"

1988 Honda CR250RJ
1983 Honda CR480
1981 Can-Am 250 MX6-B
1979 Honda CR250RZ
1979 Kawasaki KX250 A5
1978 Husky 250CR
1978 Honda CR250R
1977 Yamaha YZ400D
1977 Suzuki RM125B

J: You may have tried to outtrick yourself. I have had great success keeping the 83 stem and bearings intact as well as the 78-80 races. Put into place and add 3 washers after you tighten the spanner nut. I tighten as much as I can before I can actually feel bearings. This will help with head shake. I then add the washers and tighten down the upper clamp. This has worked for all the guys a race with (ACRMX). You have to remember to drop your forks down whatever the spacer amount was to balance the front to rear end. I do know Rick Horvat does it the way you are trying to do it. Good luck.

Daniel,

Thanks for the info. It's never tough for me to out smart myself. I'll switch back to the orginal stem, but I may still have the problem with the lower race (hopefully not!)

So the 83 bearings will match up to the 78-80 races?

J

_________________
#829 The "Factory Novice"

1988 Honda CR250RJ
1983 Honda CR480
1981 Can-Am 250 MX6-B
1979 Honda CR250RZ
1979 Kawasaki KX250 A5
1978 Husky 250CR
1978 Honda CR250R
1977 Yamaha YZ400D
1977 Suzuki RM125B

Yes

_________________
Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF